Pneumatic fan.



. copending application CHARLES KUDRER, OF ALLEGHENY, PENNSYLVANIA.

PNEUMATIC FAN.

No. 874,212. Original application filed January 9, 1906, Serial No.295,284.

To all whom 'it may concern:

Be it known that l, CHARLES KUDERER, a citizen of the United States,residing'at Allegheny, in the county of Allegheny and State ofPennsylvania, have invented new and useful lm rovements in PneumaticFans, `of which t e following is a specification.

This invention relates to pneumatic fans.

A fan involving my invention may be ut' to several advantageous uses,one of whic iis as a part of the ventilating system of a mine, such forexample as fully set forth in my for patent for ventilating apparatus,filed January 9, 1906, Serial Number 295,284, of which the present caseis a division. l provide an article of the character set forth which issimple in construction, effective in operation and strong.

ln the drawings accompanying and forining a part of this s ecification lshow in detail oneform of em odiment of the invention which to enablethose skilled in the art to practice said invention will be fully setforth in the following description, while the novelty of said inventionwill be included in the claims succeeding said description.

Referring to the drawings, Figure 1 is a sectional side elevation of afan including my invention. Fig. 2 is a transverse sectional yview ofsaid fan.

Like characters refer to like parts throughout the figures.

The fan shown is denoted in a general way by 2. The casing for the fanmay be of any desirable character, the one shown being designated in ageneral way by 3. The fan shaft which in practice is su ported in somesuitable way for rotation is enoted by 4 and may be driven in anydesirable way. Fastened in some suitableway to said shaft are the hubsof spiders as 5,the spaces betweenthe arms of said spiders serving forthe entrance of 'air into the fan which air initially passes through theinlets 6 in the opposite sides of the casing. The rims of the spidersare designated by 7 and ordinarily, but not necessarily, are ofpolygonal form, an octagonal shape being satisfactory. Between the tworims 7 and the casing 2 l may interpose packings as S to provide air tiht joints therebetween. The sides of the lan are designated by 9, theybeing of angular form, in parallelism and surrounding the two rims 7.Said sides 9 are separated from the. sides of the casing `3. Theimpelling blades or vanes of Specification of Letters Patent.

Divided and this application filed October 20, 1906. Serial No. 339.862.

' tened Patented Dec. 17', 1907.

the fan are designated by 10 and in the present instance are ofsubstantially obtuse angular form in cross section, although the twobranches thereof merge upon a curve instead of u on an angle. As a meansfor convenient ymounting these blades or vanes in place l may provideangular strips as 11 arranged in transversely alined relation; that is,one

`strip 11 will be directly opposite a similar and cooperating strip, ablade as 10 being fasto the two opposite strips. One branch of each pairof strips 1l is fastened to the external surface of the rim 7, while theother branches thereof are fastened to the inner faces of the two sides9 for which purpose rivets, bolts or other suitable means may beprovided. To each face, therefore, of each rim 7 is attached one branchor arm of a strip 11. These strips are preferably angular in crosssection to' provide for their ready mounting in A)lace and for theproper connection therewit of the impelling blades or vanes 10.

The space between the extreme inner ends of two adjacent blades or vanesconstitutes a throat for the passage of air. This air may pass inopposite ldirections through the said throat as will be obvious. lprefer to make the spokes or arms of the spiders 5 of V form or wedgeshape in cross section and to face the apexes of the V portions outwardas in this way l secure the least possible resistance to the incomingair. By making the spokes or arms in this shape l also provide strength.

Between each two opposite blades or vanes 10 l arrange blades as 12 ofangular form in cross section and each consisting of an elongated bodyportion provided with an inwardly extending portion which in the presentcase is substantially radially disposed of the fan 2. The forward endsof the bodies'of the blades 12 are tightly fitted against the blades orvanes 10. These blades 12 also extend from one side 9 to the other side9 of the fan casing and each of them with an adjacent and coperatingblade or vane 10 provides a pocket which l will denote by 13. Thesepockets are filled with air which is compressed therein, the compressedair serving to 4cushion the air which enters the fan 2 under highvelocity. As will be apparent, the blades 12 are fitted to the blades orvanes 10 and extend rearward from the latter and then inward. The blades12 may besecured in position in any desirable way; for example, they maybe fastened to the angularly shaped strips 14 which in turn are fastenedto the inner surface of the fan sides 9.

I have stated that the shaft 4 may be driven in any desirable way, forexample, I may use a steam engine or an electric motor for such purposeto turn the fan in the direction shown by the arrow in Fig. 1.

The blades 10 are gral with the shanks or bodies 10, as shown clearly inFig. 1. These Shanks or bodies 10 extend outwardly from the shaft 4 andare disposed radially or substantially radially of the fan andconstitute in effect continuations of such blades.

It will be evident from what has been stated that the blades of my fanwheel have pockets at their rear sides. in the present case are situatednear the outer ends of said blades, subserve a very important function.The air entering the fan travels at a high velocity; at times in theneighborhood of 3200 feet a minute. This air enters the pockets and iscompressed therein and it serves to cushion the rapidly' moving streamsof air. The air expands as the pockets revolve away from the point ofcut-off thereby giving to the air a continuous and uniform velocity ofdischarge out of the fan wheel into the fan housing or casing.

What I claim is:

1. A fan involving a casing and blades, blades extending rearwardly fromthe firstmentioned blades, near the outer edges thereof and providedwith inwardly extending portions to furnish pockets on the rear of saidrst-mentioned blades.

2, A fan involving a casing and blades, said blades having pockets ontheir rear sides preferably formed intex These pockets, whichr toreceive and compress air which acts to cushion the air entering saidfan.

3. A fan having spiders and sides, angular strips fastened to the sidesand spiders, re-

) spectively, angular impelling blades connected to said strips andextending from one side to the other, and angular blades fastened tosaid sides and fitted respectively against the rear faces of thefirst-mentioned blades and forming with the latter pockets.

I 4 A fan having a shaft, spiders fastened to said shaft, sides unitedwith said spiders, shanks or bodies extending outward from the shaft anddisposed substantially radially of the fan, angular impelling bladesjoined to the outer ends of the respective shanks or bodies and integralwith the latter, and substantially angular blades fastened to the rearfaces of the impelling blades and forming with the latter pockets, allthe blades extending from one of said sides to the other.

5. A fan wheel having sides provided with eyes and also having bladesextending from the central portion of the fan uninterruptedly alongirregular planes to the peripheries of l the respective sides, andangular blades connected with the outer ends of the first mentionedblades on the rear sides thereof and their free portions extendingsubstantially l radially toward the axis of the wheel, the

i several blades presenting air-receiving pockets.

In testimony whereof I have hereunto set my hand in presence oftwosubscribing witnesses.

CHARLES KUDERER.

Witnesses z f T. BROWN, I ALFRED OEI-ILER.

